Patent GB-1475005-A (GB)
Title: Mechanism for truing disc-like abrasive tools
IPC: B24B53/04
Filed: 1974-12-12
Abstract: 1475005 Trueing grinding wheels EXPERIMENTAL N I INST METALLOREZHUS STANKOV 12 Dec 1974 53813/74 Heading B3D A mechanism for trueing a disc-like abrasive tool 2 for use in cutting a straight bevel gear 3 in a machine 1 operating on a profile generating principle is mounted on a carriage 4 for carrying the tool and provided with trueing elements drivable along paths corresponding to the cutting profiles of the tool by a self-contained means, the trueing elements also being movable in directions parallel and normal with respect to the axis of rotation of the tool. The tool is mounted on a spindle 9 rotatable in a sleeve 8 movable axially relative to the carriage 4 by the operation of plungers 12, ... 15 movable in cylinders 11. A key 12 is axially fixed in a slot 16 in the sleeve. A housing 18 is generally H-shaped to form two compartments, in one of which the carriage 4 is located and in the other of which a slide 20 is mounted for movement along guides 21 normal to the axis of the tool. The slide is movable by rotation of a nut 25 which is mounted in the key 17 and has a wheel engaged by a worm 50 on a shaft 51 extending outside of the housing for manual rotation, the nut engaging a screw 26 having a ratchet wheel 27 and stopping wheel 28 mounted in the slide 20 by a holding cap 29, a guiding bar 30 and a T-shaped housing 31. A locking member 32 is spring loaded into engagement with the ratchet and fixed to the bar 30. The trueing tools are in the form of diamonds 5<SP>1</SP>, 6<SP>1</SP>, 7<SP>1</SP> carried by levers 5, 6, 7, the lever 7 having a bracket carrying a pawl 34 engaging the ratchet wheel 27 and being movable along guides 53 in the T-shaped housing 31. A rack 7<SP>11</SP> is cut into the side of lever 7 and engages a central gear 37 which also meshes with a rack 38<SP>1</SP> formed on a plunger 38 of an hydraulic cylinder, movement of the plunger thereby causing movement of the tool 7<SP>1</SP> parallel to the axis C to effect trueing of a cylindrical surface a of the tool. The gear 37 is mounted on a shaft having gears 45, 46 fixed to its ends, the gears meshing with racks 47, 48, respectively, formed on the levers 5, 6 carrying the tools 5<SP>1</SP>, 6<SP>1</SP>. The walls of the slide 20 and a wedge-shaped portion of the T-shaped housing 31 define slots 55, 56 accommodating guides 57, 62 along which the levers move upon rotation of the gears 45, 46. Guide 57 is rotatably adjustable by the opposed action of screws 60, 61 about a sleeve 59 in housing 20, and guide 62 is likewise adjustable about a sleeve 64 to determine the paths, and hence the angle of the tapered surfaces b formed on the tool, of the trueing tools 5<SP>1</SP>, 6<SP>1</SP>. In operation, the guides 57, 62 are adjusted to the required angles by screws 60, 61, 65, 66 and the sleeve 8 is moved to an upper position by operation of the plungers 12, 13, the key 16 moving the slide 20 a corresponding amount. The plunger 38 of the cylinder 23 is moved to its lower position so that the rack 38<SP>1</SP> turns the gears 37, 45 and 46 and move the levers 5, 6, 7, the lever 7 causing the panel 34 to rotate screw 26. Rotation of worm 50 manually adjusts the slide 20 along its guides 21 normal to the axis of the grinding wheel until the end of the T- shaped housing 31 engages an end cover 22 of slide 20; the levers 5, 6, 7 and slide 20 are then in an extreme initial position. When plunger 38 is moved slowly to its upper position, the rack 38<SP>1</SP> turns the gears 37, 45 and 46 so that the tools 5<SP>1</SP>, 6<SP>1</SP>, 7<SP>1</SP> simultaneously true the surfaces a, b of the tool. The plunger 38 is then moved in its reverse direction and, when the tools have cleared the surfaces a, b, the pawl 34 acts to rotate screw 26 to advance the slide 20 a predetermined amount.